Digital TV – Terrestrial (DTT)

If a problem has just started, the answer may lie in your set-top box, your aerial or your local transmitter. Try narrowing this down:

• Check today's transmitter work to see if your local transmitter is affected by a fault or maintenance work.
• If possible, see if the problem is affecting another set receiving digital TV through a different aerial - for instance, at a neighbour's.

If you share a communal aerial (for example, in a block of flats) and others using the same aerial are also having problems, you should contact whoever is in charge of your building - the landlord, council or property manager.

If the picture is breaking up or freezing, or if the picture and sound are out of synchronisation:

• Try resetting your set-top box or digital TV.
• If you have a set-top box (not a digital TV), see if the analogue picture is affected too. If so, it may be caused by interference from radio or electrical equipment, or there may be a problem with your aerial.
• Very occasionally, unusual atmospheric conditions (high air pressure) may cause picture break-up or even complete loss of reception. The only solution is to wait for the weather to change.

If you are not receiving channels you think you should have:

• Check today's transmitter work to see if your local transmitter is affected by a fault or maintenance work.
• Try resetting your set-top box.
• If that has no effect, there may be a problem with your aerial or a fault in your equipment.

Working out which channels are missing could help pinpoint the problem. Digital TV channels and radio stations are broadcast in groups known as multiplexes.

Check the full list of channels in the UK national multiplexes. If all the channels in one of these multiplexes are missing, the problem may be in your aerial or its connections. To have an outdoor aerial checked, we suggest you contact a professional aerial installer, either one registered with the CAI (Confederation of Aerial Industries) or a Registered Digital Installer.

If you can receive some of the channels in a multiplex but not all, the problem is more likely to be in your set-top box or digital TV set. Please contact your retailer or the equipment's manufacturer.

If your area is covered by more than one digital transmitter, your set-top box or digital TV may pick up signals from the wrong one. When searching for available channels, it scans from the lowest channel number to the highest. It will tune to the first signal it finds and may ignore one at a higher frequency, so you may get channels from the wrong region or you may not get the strongest signal.

To receive the correct signals, you need to make sure your aerial is in the best condition and pointing towards the correct transmitter.

If you are confident about setting up your set-top box or digital TV, you can manually retune it to the correct channels. See your instruction manual for details, or contact the manufacturer. To find the channels and transmitter for your area, use the Digital UK postcode checker and, on the results page, click on Trade view (alongside the Postcode checker results heading).